While some vehicle wheel balancing machines are operative to support a vehicle wheel having a tire mounted thereon and spin the wheel and tire at high speed while at the same time determining at which positions on the periphery of the wheel rim balancing weights should be added to dynamically balance the tire and wheel assembly, machines of this type are very expensive and thus are not used by small tire shops and service stations or garages.
More frequently, wheel balancing machines for dynamically balancing vehicle wheels having tires mounted thereon are of the type including a motor driven friction wheel for spinning the associated wheel and tire assembly on a vehicle and a vibration pickup pad is attached to the support structure for the wheel being spun. However, such devices may not be readily utilized in conjunction with the front wheels of four-wheel drive vehicles and on spare wheel and tire assemblies without mounting the spare wheel and tire on the vehicle.
Accordingly, there is a need to provide an apparatus whereby the front wheel and tire assembly of four-wheel drive vehicles and the spare wheel and tire assemblies of other vehicles may be rotatably supported, as though mounted on a vehicle, and in position to be engaged and driven by a motorized friction drive assembly of the type herein abovementioned and also with the support structure for the wheel being spun including means for supporting a pickup pad thereform.
Previously patented devices including some of the structural and operational features of the instant invention are disclosed in U.S. Pat. Nos. 2,349,552, 3,452,603, 3,578,045 and 3,581,576. However, these previously patented devices, for various reasons, are not readily adaptable to perform all of the functions of the instant invention.